Technology has been one of the driving forces of globalisation, but now developments in three dimensional printing could give a boost to the counter-movement.
Computer ‘printers’ that can build objects in 3D by accurately adding thin layers of material on top of each other date back to the 1980s. The technologies used include fusing a layer of powdered material with a laser, dispensing melted plastic through nozzles, and photo-curing resin.
Early 3D printers were big and expensive, but prices have fallen below £1,000 for models that print small plastic objects, while more expensive devices can ‘print’ in other materials including metals and textiles.
PA comments:This opens the floodgates to a vast range of applications, from customised automotive and aviation components to prosthetics and orthopaedic implants. The ability to localise manufacturing will change import and export world dynamics, because communities will be able to make what they need, says Daniel Toon, technology innovation consultant at PA Consulting. People living in remote areas could manufacture their own things.
3D also makes it possible to produce complex shapes. “You can print objects you can’t mould,” says Chicago-based Russ Schreiner, director of advanced process development at GN ReSound, a pioneer of 3D printing in the production of hearing aids.
Last year, surgeons created a replacement jaw for an 83-year old woman in titanium that took 33 layers to form each 1mm of thickness. In future, scientists plan to build layers of living cells to print synthetic body organs.
Another big advantage of 3D printing is that it becomes economically viable to create one-off objects. BAE Systems uses it for rapid low-cost prototyping of small fixtures for aircraft such as the Tornado, Typhoon and Hawk, and for creating single-use tools for components and ground maintenance.
The advantage is being able to get the design right first time, says Mike Murray, head of airframe integration at the company’s Military Air and Information (MAI) division. Tools and components can now be produced up to 70 per cent faster, he estimates.
Overall, MAI’s product development has been reduced from six months to a couple of weeks because there is no need for tooling to create components—items can be designed one day and printed overnight for use the next day.
It is also much cheaper. “We can try fixtures out on aircraft in thermoplastic for less than £100 and be sure they fit correctly before we make the metal equivalent,” Mr Murray says.
GN ReSound was one of the first to use photo-curing printers in large-scale manufacturing, and now produces batches of 40 individualised hearing aids in 90 minutes. It has also pioneered global manufacturing by sending 3D images between its facilities in China, the UK and the US.
“We can move production around the world, depending on which centre of excellence is appropriate,” says Mr Schreiner.
The more you use 3D printing, the more innovative ideas you have for applications, says MAI’s Mr Murray. His team built protectors for use on auxiliary power shafts, to prevent expensive damage that is often caused when engines are removed during maintenance. The team has also made inspection gauges to check door apertures and alignment.
GN ReSound is currently developing soft hearing aids, and in-ear speakers for personal stereos and mobile phones. The military is also interested in the in-ear devices for communications and hearing protection.
As 3D printers can not yet build soft silicone products, GN ReSound is using them to make hard injection moulds that can be filled with liquid silicone and removed when it has set.
PA comments: Many structures can be built better using 3D printing than with traditional manufacturing processes, because you can do much more with the design, says Dr Toon. This design freedom means that engineers can emulate the mechanical supremacy of complex organic structures that have evolved to be as strong or rigid as they need to be.
Instead of building a bridge by bolting together girders, the structure could be designed to support loads using optimised geometry and material properties.
Using 3D printing is also much more environmentally friendly, because it produces much less waste then the cutting and grinding of traditional manufacturing.
In the future it will be possible to build very large products in 3D using multiple materials. Scientists are studying termite mounds to understand how they manage the 3D environment to dissipate heat and keep temperature constant despite the thousands of termites living within them.
The result could create a model for building homes on a large scale for people living in the favelas of Brazil, explains PA.
Materials that can be used in 3D printing are evolving fast. But before they can be exploited for practical applications their physical properties have to be tested. MAI is only using 3D to create non-structural components in plastic at present. “But we are starting to look at metals such as titanium as a replacement for castings,” says Mr Murray. Printing structural metal components for in-flight use is at least five years off he thinks.
3D printing enables shoes and clothing to be customised to individual’s physiology. By the 2016 Olympics, athletes will almost certainly be using sports equipment optimised to their performance, predicts PA.
It could be like going back to cottage industries, pre-industrialisation. A local electronic ‘cobbler’ could make people customised shoes at mass market prices in a fraction of the traditional time for a bespoke item. The revolution that PCs and printers brought to the information industry, could be repeated in manufacturing.